The following was provided by the state via email:
The licensee discovered a damaged Am-241 alpha source during a routine sealed source inventory and leak test on Monday February 23, 2009. A pinhole leak was discovered through the source active area. After further assessment on February 24, 2009, it was determined that more than half of the source activity cannot be located.
The Am-241 source was manufactured by North American Scientific (model # CAL2702, source #67250) with an activity of 845.8 nCi (nanocuries) as of October 1, 2005. Currently there is 160 nCi remaining on the Am-241 source and 160 nCi of contamination on the sponge insert in the source container. 521 nCi of the activity cannot be accounted for.
The licensee has performed preliminary contamination surveys of the source storage area, source use area, and the common lab area. The survey were performed using GM survey meters with pancake detectors and wipes counted with a liquid scintillation counter. No significant contamination was found.
The licensee will perform additional surveys and continue to investigate the cause of this incident.
THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than
IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as
moisture density gauges or thickness
gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks.